Ervin Kosi completed his secondary education in June 1991. He got his first job at Kozina Police Station before joining the Ljubljana Mounted Police Station. In 1995, he moved on to work for the Slovenian Intelligence and Security Service of the Ministry of Defence, where he performed various jobs and tasks, including in management positions within the Ministry.

In 2004, he pursued his career at the Agency of the Republic of Slovenia for Agricultural Markets and Rural Development in the Direct Payments Division, working in a variety of areas and performing various managerial tasks. In November 2018, he was appointed Deputy Director-General of the Agency for Agricultural Markets and Rural Development. Between October 2020 and April 2021, he was the Agency’s Acting Director-General, then again Deputy Director-General until 15 May 2024, when he became State Secretary at the Ministry of Agriculture, Forestry and Food.

He completed his studies at the Short-Cycle Administrative College in 1997 and the Administrative College in 1999, both while working. In 2002, he enrolled in the postgraduate master’s programme Governmental and European Studies, which he successfully completed in 2006.